Screw-driving mechanism.



F. W. RUSSELL. SCREW DRIVING MECHANISM.

'APP LIOATION FILED JAN.17, 1912.

1 082 771. Patented Dec. 30, 1913.

2 SHEETS-SHEET 1.

Envewfofl map-(Mia W654 W P. W. RUSSELL' SCREW DRIVING MECHANISM.

APPLICATION IILED JAN.17, 1912.

Patented Dec. 30, 1913.

2 SHEER-slum: 2.

mm @2440 M rnnnnruc WILLIAM RUSSEL/L, or nnnm'rcn, ENGLAND.

' SCREW-DRIVING MECHANISM.

Toall whom it may concern:

Be it known that I, FREDERIG WILLIAM RUssELIL, a subject of the King ofEngland, residing at .135 Howell road, 'Reddltch, Worcestershire,England, have invented certain new and useful. Improvements in screwDriving Mechanism, of which the following is a specification.

Thisinvention has for its object the production of an efficient andinexpensive screw-driving mechanism which shall be an entirelyself-contained attachment adapted to be used in an ordinary sensitivedrilling machine, to which it maybe secured merely.

1 by fixing its shank in'the machine spindle or chuck, as in the case ofan ordinary drill or certain well known tapplng and stud settingdevices; no other attachment to,.nor

any modification of, an ordinary drilling machine being, required.

The screw-driving mechanism herein referred to is designed to have selffeeding of screws, and is primarily intended to deal with ordinary woodscrews having either round or countersunk slotted heads, but it will beunderstood that the device may also be used for inserting suitablyshaped screws into tapped holes in metal articles. As in such work it isfrequently necessary to drive successive screws into pieces of work ofdifferent heights from the machine table, I

particularly desire to produce a device in which the delivery membershall automatically be brought into correctposition relative to thework, thus avoiding the necessity of separately adjusting either themachine table or the delivery member to each variation in the work,before a screw can be driven; as is the case in certain exist-inscrew-driving mechanism.

In order to explain clearly this my invention I have appended hereuntothree sheets of drawings with figures and numbers of reference, eachnumber denoting the same driving mechanism made according tomyinvention. Fig. 2 is a plan showing the I tail rods and the attachmentof their forks interior. (Figs. 5 to 11 are drawn to an en-Specification of Letters Patent. Iateflted Dec,

Application filed January 17, 1912. Serial No. 671,677.

larged scale.) F 5 is a sectional View of the escapement mechanism, andshows the same as arranged 1n connectlon wlth the supply bin. Figs. 6and 7 are plans of the escapement device. Fig. 8 shows the guide stirrupattached to the delivery member.

Fig. 9 is a plan of the guide stirrup. Fig. 10 shows the clutchmechanism. Fig. 11

-1llustrates I the torsion-adjusting device. Fig. 12 1s a. view ofthepeg key used in connection with the torsion adjusting de- .vice. Fig. 13is a sectional elevation of another form of a screw-driving deliverymember. Fig. 14 is a" similar view, but shows the mechanism in analtered position, partof the screw-driving spindle being broken away.Fig. 15 is a plan of the threejaws of the screw-driving delivery member,and Fig. 16 is an inverted plan of the body of the said member. Figs. 17and 18 are respectively side and end elevations of the lower end of thescrew-driving spindle, provided with a floating tip. Fig. 19 is asimilar view of Fig. 18, but shows the spindle partly in section inorder to clearly expose the sliding shank of the tip.

In the accompanying drawings 20 is a continuously revolving member whichmay be of cylindrical form, and is adapted at its top end to be readilyattached to the chuck or, as in the example selected for illustration.spindle end 21 of an ordinary sensitive drilling machine. Extendingdownward from the continuously revolving member 20 is the intermittentlyrevolving member 22. The attachment of the member 22 to the member 20,is such as to provide a bearing which permits the two members to revolveindependently of one another, but at the same time maintains themstrictly in line. at prevents end play or independent longitudinalmovement.

The lower end of the continuously revolving member 20 is provided withsuitable clutch teeth 24 which are adapted to engage with similar teethformed upon the clutch collar 25. which is-movably mounted upon theintermittently revolving member 22. The movements of the'clutchscollar25 are guided and limited by'its angular slot 27 (Fig. 10) working uponthe pin 26 which projects fixedly fromthe intermittently revolvingmember 22.

der of an enlarged portion or boss formed upon the said intermittentlyrevolving member. Extending downward from the lower end of theintermittently revolvin member l2 and rigidly secured thereto,-is t escrewdriving spindle 23, of which the lower extremity 34 is adapted toengage with ordinary slot-headed screws.

The bottom surface of the torsion-collar 29 may be. provided with anumber, usually eight, of radial grooves or channels 30, one or more ofwhich are normally engaged by suitable projections from theintermittently revolving member 22; such projections may convenientlyconsist of a pin 31 driven into the intermittently revolving memberimmediately above its boss hereinbefore referred to. Also upon this sameboss is marked a single longitudinal zero line 32 which normally is inagreement with one of a series of numerals which are marked upon theoutside surface of the torsion-collar between the grooves therein, andagreeing in number with the said grooves. At the top end of the zeroline and immediately adjacent to that ed e of the boss upon which thetorsioncollar a uts, is a small groove or hole 33 cut radially into theboss.

Mounted fixedly upon the continuously revolving member 20 and near theupper end thereof, is the eccentric sheave 35, upon the circumference ofwhich is the ring or bush 36, so fitted as to form a bearing in whichthe eccentric sheave may revolve freely. Secured to the outside of thisbush 36 (for instance by means of four stay bolts 37) and so surroundingthe continuously revolving member, is the supply bin 38 which is anannular receptacleopen at the top and having a bottom which formsoneturn of a right-hand spiral, the lowest point of the bottom beingapproximately underneath the highest point thereof, the upper and lowerends of the bottom usually being connected by a vertical and radial endplate 39. The bottom of the annular supply bin need not in all cases bea spiral of uniform pitch; I may if desired allow a certain portion ofthe bottom'to be quite flat, and I usually make the lower side of thespiral, for a certain distance from its junction with the end spiral. Acircumferential'slot 40 is formed in'thebottom of the annular supply bin38,

usually about mid-way between the inside bottom, immediately inside theend plate 39. To

The annular supply bin may also be pro vided with a return plate 42which forms a segment of a left hand spiral and constitutes a sort ofinner bottom to a portion of the said "annular bin, the upper end ofthe, re-

turn plate abutting upon the upper end of the annular and spiral bottomhereinbefore described, and the lower end meeting the inclining side ofthe said bin bottom at a suitable position 43. A cavity 44 is providedin the lower end of the return plate, near its junction with the slottedbottom of the bin, in such a way as to form a-sort of arch across thesaid slot 40. I also may provide a headplate '45 which is situated 35above and near to, and parallel with the lower end of the bin bottom,and extends from the end plate 39 to a position near the juncture of thereturn plate 42 with the said bin bottom. This head plate 45 is shown inthe drawings partly broken away in order to expose the slot 40 and hole41.

At the lower end of the spiral bottom of I the supply bin, in immediateproximity to theend plate 39 is the small tubular part 46, the top endof which-fits into the hole 41 in the bottom of the bin, the tube 46being approximately at right angles to the surface of that portion ofthe spiral in which the hole 41 is situated, and the top end of the saidtube abutting upon the under side of the head plate 45. This tube 46 hasa longitudinal opening in its upper side, that is the side which facestoward the circumferential slot 40 in the bin bottom. .The two edges ofthe said opening in the tube 46 are provided for a suitable part oftheir length with side platessor wings 47. J oining together the lowerportions of the two wings 47 isthe bafiie plate 48 which is arranged 119at an angle with the longitudinal direction of the tube 46 in such "amanner that the bottom end of the baffle plate coincides with thecircumference of the tube, but its top end is some distance outside suchcircumference.

Embracing the tube 46 immediately below the bottom of the supply bin andabove the upper edges of the wings 47, is the escape-. ment 49, which isa fiat piece of metal suitably mounted upon a center pin 50 about whichit may have a certain amount of movement in its own plane. Theescapement is provided with projections 51 and 52 adapted to control theopening into the tube 46, and also with a slot 53 which accommo- 12.5

dates one end of the crank lever 54 which works upon a fulcrum pin 55-and is acted upon by a suitable spring 56 (indicated by dotted lines).

The tubular part 46 and the escapeinent' 1130 center pi-n 50 may both besupported by a bracket 57 which. may also support the crank leverfulcrum 55 by means of a suitable lug 58. V

Extendin downward from the tubular part 46 is the deflection tube 59which may conveniently be flanged-and bell mouthed at its top end whichis pressed by a short spiral spring 60 supported by a union nut m 61against the underv face of a flange 62 which is mounted or formed uponthe tubular part 46 at or near its lower end.

Mounted upon the screw-driving spindle 23 is the delivery member, thebody 63 of which according to Fig. 1 approximates to a cone in shape andis bored through vertically to form a bearing in which the scr wdrivingspindle may both revolve and slide freely. Extending in an upward andslanting direction from the body of the delivery v member-is thedowntake tube 64, the upper end of which is made bell-mouthed orfunnel-shaped. The bore of the downtake tube 64 runs into the verticalbore of the deliv- 55 ery member body. The bore ofthe downsuitableyielding jaws 65. Suitably and rigidly connected with the downtake tube64 is the small horizontal plate or flat topped bracket 75.

Secured to' the delivery member body at 76 are two-vertical guide barswhich may suitably consist of the two sides of a stirrup 76, the top ofwhich is square with the sides but is bowed outward so as to clear thecon- ,tinuously and intermittently revolving mem here and 22. Thevertical sides of the guide stirrup 76 are accommodated in suitableholes or slots 77 formed in the aide plate 78, the bowed top of thestirrup eing above the said guide plate which is mounted upon theintermittently revolving member 22, so as to be arevolving fit. Theguide plate may suitably be kept in position by the lower edge of theboss on the member 22 hereinbefore referred to, and acollar or a knurlednut 79.

In order to prevent thedelivery member I from revolving with thescrew-driving spindle,-'I provide a tailrod 80which may conveniently beforked and may be secured di- 5 rectly to the delivery member, althoughI usually prefer to attach it to the guide plate 78 as shown in thedrawings. It is also re quired to prevent the supply bin 38 fromrevolving, and for this purpose I may provide 0 a second tail rod 81,one end of which is 6 may conveniently be attached loosely to a suitableortion of -the lower tail rod 80 hereinbe ore referred to. y

The action of a magazine screw-driving machine attachment made accordingto Figs. 1-11 is asfollowsz-The shank 21 is secured in the spindle orchuck of an ordinary sensitive drilling machine, and the tail rod 80 isallowed to rest against the frame-work or; column of such a machine; theend of the said tail rod may be supported by a piece of strin or wireshould the construction of the mac ine be such as to render thisdesirable. On the machine being set in motion the continuously revolvingmember 20 is caused to revolve, and transmits its motion to theintermittently revolving member .22

and screw-driving spindle 23, by means of the clutch 24, spiral spring28, and torsion collar 29; the spring 28 being wound up so as to offer.conslderable torsional resistance. The delivery member does not revolveowing to the guide stirrup 76 and guide plate 78 being held by the tailrod 80. The supply bin 'also is prevented from revolving by means of thetail rod 81, bolt owing to the eccentric revolving with the member 20,an eccentric or irregular sifting motion is imparted to the said supplybin. A number of screws, as for instance one gross, of the size andpattern with which the device is constructed to deal, may be depositedin the supply bin 38, and owing to its sifting motic-n are caused toslide and roll around in it in the direction indicated by an arrow inFig. 4. Many of the screws fall into the slot .40 which is large enoughto loosely inclose the necks of the screws, but, will not allow theheads to pass; consequently these screws hang point downward from thebottom of the bin and move circumferentially along the slot. On reachingthe lowerend 43 of the return. plate 42, such screws as remain.uncau'ght by the slot, slide or roll up the in-- cline of the saidreturn late and are so sifted around until they all into the slot, whentheirheads are able to pass through the gap or arch 44, so that suchscrews continue to travel down the spiral until the foremost one isarrested by the point 51 which is normally in the position shown in Fig.6. Screws between the escapement and the arch 44 are prevented fromriding or shaking up by the head-plate 45.. Upon the operator loweringthe drilling machine spindle, the delivery member nozzle comes incontact with, and is arrested by, the object into which screws are to bedriven, and this 'screw-drivingspindle slides downward into the saiddelivery nozzle thus closing the bottom of the downtake tube 64. I Thismove- -ment brings the bracket 75 into contact with the lower end of thecrank lever 54, causing means of the slot 53, brings the escapement intothe position shown in Fig. 7 By these the latter to move upon itsfulcrum, and by means the foremost screw is allowed to slide into thetube 46, while the next screw 1s arrested by the 'oint -52 of theescapement.- It.wi-ll be seen t at as thebracket 75 is approachedby thecrank lever 54 the funnel shaped top of the downtake tube 64 inclosesthe bottom end of the deflection tube '59 (which owing to its flexiblemounting allows for the sifting motion of the supply bin), consequently,as a screw is passed by the escapement there is a practically continuoustube down which it slides pointforemost until it is arrested by thescrew-driver spindle at thebot-tom of the downtake tube. The operatornow raises thedrilling machine spindle and thus withdraws thescrewdriving spindle, allowing the screw to fall into the deliverynozzle, where it hangs by Y its head with its point protruding throughthe small central hole in the bottom of the nozzle. The work is placedupon the machine table so that the protruding end of the screw I pointsupon the desired position, and the operator again lowers the machinespindle so that the end of the screw-driving spindle 23 comes in contactwith the head of the screw, the ridge 34 engaging the slot of such screwand driving it into the work. When the screw is "driven firmly home intothe worl it offers to' the screw-driving spindle such resistance as toovercome the torsion of the spiral 'sprin 28. The screw-driving spindleand the intermittently revolving member become stationary, and theclutch collar 25 driven by the continuously revolving member 20 attemptsto over run them and further wind up the spring. But as soon astheclutch collar 25 commences to over run the intermittentlyrevolvingmember 22, the pin 26acting in the slot 27 draws the clutch collar downand so disengages the clutch teeth 24. But the clutch collar thus beingreleased from the driving power of the continuously revolving member,the spring re-asserts itself and the clutch is ree'ngaged only to bethrown out of gear again, and again reengaged, thus producing achattering sound which notifies the operator that the screw is drivenhome. As one screw is being driven into the work, another screw ispassed by-the escapement and slides to the bottom end of the downtaketube, from which it drops into the nozzle as the spindle is raised thuseach successive lowering of the machine spindle after the first, drivesa screw, until the supply bin is empty. The spring 56 causes theescapement to return to the position shown inFig. 6, each time the cranklever is withdrawn from contact with the bracket 75. The wings 47 guidethe lower ends of the screws into the tube 46 and the bafile plate 48counteracts a tendency of the screws to fallhead foremost as they arepassed by the escapement. The withdrawal of the screw-driving spindlefrom the delivery member is limited by'the bowed top I then allowing itagain to engage with the projection 31. This operation may convenientlybe accomplished with the aid of a peg key Fi 12 one peg being insertedin the hole 33 w ile the other. peg enters one of the adjacent grooves30.

It will be understood that in order to insure the screw-driving bladereadily engaging with the slot in the screqw-head, the tube in whichthis takes place must be of approxi- 'mately the same diameter as suchscrew heads. But I have found it to be the case that a considerableproportion of ordinary Wood screws have their heads of slightly faultyand irregular formation, some being above their standard in size andsome having their slots not quite central. The heads of such faultyscrews if introduced into a screw-driving mechanism are liable to jam inthe delivery tube, causing frequent delay and sometimes considerabledamage to the mechanism.

In Figs. 13 to 16 an improved delivery member is shown which shall beable to deal with faulty screws without danger or delay or injury. 63 isthe delivery member body in the central bore of which the screw-drivingspindle may slide and revolve freely. Extending in an upward andslanting direction from the lower part of the body is the supply tube 64the bore of which is someforms a continuation of the vertical bore ofthe body, and in which the screw-driving spindle may slide and revolve.The bottom ends of the jaws project radially inward so as to restrictthe bottom outlet from the inclosed cylindrical chamber, and thusprovide (when in the normal position) the small central hole 85.Extending rigidly from the jaws in an upward direction are-the jawshanks or levers 86 which may conveniently be of rectangular section,and are accommodated in suitable radial slots or grooves 87 formed inthe outside surface of the body. Suitable lugs 88 formed at the sides ofthe grooves 87 carry the fulcrum pins 89 on which the jaw shanks aremounted.- The .top ends of the jaw shanks have inward ra- 7 reason oftheextra pressure of the inward of the radial projections 90 of the jawshanks abut upon t e conical portion-of the plunger 92 which encirclesthe screwdriving spindle .and has its bottom end accommodated in acylindrical recess formed in the top endof the body 63. The top end ofthe plunger extends upward, in the form of a small tube, and upon it-issecured the plunger cap 93 the edges of which extend downward so, as toabut upon the chamfered portion 91 of the jaw levers. A spiral spring 94tends to force upward the plunger 92 so that its conical portion pressesthe top ends of the jaw levers outward and so hold the jaws closelyshut. 1

Theaction of this device will be easily understood and is as follows:-The screwdrivin'g spindle being in the raised position shown in Fig.1-, a screw is caused to slide point first down the supply. tube 63 andfalls into the nozzle, its point protruding through the small centralhole 85. The operator lowers the revolving screw-driving spindle so thatits end comes in contact with the head of the screw, engaging the slotand driving the screw into the work. As the screw is being driven intothe work the boss or collar on the descending. screw-driving spindle,comes in contact with and presses upon the top of the plunger cap 93,compressing the spring 94 and removing the conical part of the plungerfrom its contact with the inward extensions 90 of the jaw levers, asshown in Fig. 14. At the same time the edge of the plunger cap 93descending upon the ch-amfered parts 91 of the jaw levers, draws theminward and thus opens the jaws, allowing the head of the screw topassout of the nozzle. Should a faulty screw, as hereinbefore referred to,be allowed to slide into the nozzle, and should such screw on beingengaged by the screw-driver require more room in which to revolve thanis normally provided in the nozzle, then the screw expands the nozzle toaccommodate itself, and this is accomplished without any distortion orinjury to the mechanism by projections 90 upon the conical part of theplunger 92 causing the said plunger to be depressed, slightlycompressing the spring 94. This spring re-asserts itself and reduces thenozzle to its normal size as soon as the faulty screw has been passed.Should a screw allowed to slide down the supply tube into the nozzle beincapable of being driven, as for instance by reason of its having noslot or being introduced head-foremost, the

operator may remove such screw without delay, merely by applying manualpressure to the plunger cap 93 which, as will be understood from thedescription hereinbefore 'set forth, causes, the jaws to open and allowsthe screw to fall out.

I have found it to be the case-that a considerable roportion of ordinarycommercially prodhced screws have the slots cut in their heads somewhatout of center, and I therefore abling suc faulty screws gaged with thescrew-driver. For this purpose I provide the screw-driver with a movableor floating blade, which normally co} incides with a diametral lineacross the working end of the screw-driver, but'which may be deflectedto one or either side of such diametral line when brought into contactwith an eccentrically slotted screw head.

In Figs. 17-19 (which are drawn to an enlarged scale) 95 is the screwdriving blade which is formed upon the under side of the flange or disk96. Extending from the top rovide improved means for en-.'

to be readily en side of the said flange 96, and diametrally 98 formedin the end of the spindle 23.

The bifurcated'end of the spindle abuts upon the top side ofthe flange96. The floating tip, which, it will be seen, consists of the blade 95,flange 96 and shank 97, is usually made from a solid piece of steel ofthe same diameter as the flange 96, and this is somewhat less than thediameter of the spindle 23 so that the shank 97 may slide transverselyin the slot 98 to the extent 05f this difterence of diameters,withoutprotruding outside the circumference of the spindle 23. Thefloating tip is maintained in place, and has its movements limited by apin 160 which passes through a suitable slotted hole 101 out in theshank 97, and has its ends rigidly secured in those portions of thespindle end which'form the sides of the slot 98. In order to give thefloating tip a tendency to remain in or return to a central position,

I may, if necessary provide a suitable indent in the top of the shank 97in combination with a small spring-inforced plunger such as 102,accommodated in a central hole extending upward from the slot 98.

What I claim as new and desire to-secure by Letters Patent is 1. In ascrew driving device the combination of a magazine for screws, a screwdriving tool, a means for delivering and prop that said tool may berotated by said spindle.

2. The combination of a rotary spindle,

a'tubular supporting member secured to said spindle, a magazine forscrews, a screwand'means for delivering and driving tool iding screws moperative relaproperly ho tion to said tool; said magazme, tool, and

tion of a magazine for screws, a screw driv-.

ing tool, a means, for delivering and properly holding screws inoperative relation to said tool and a member formingthe sufiicient andsole support for said magazine, screw delivering and holding means andtool, a rotatable spindle adapted to engage and support} said supportingmember, a screw selecting means and a means ada ted to be operated by arelative movement 0 the said screw delivering and holding means, and themagazine for causing the delivery of a screw.

4. In a screw driving device the combination of a magazine for screws, ascrew driving tool, a means for delivering and properly holding screwsin operative relation to said tool, and a member forming the sufiicientand sole support for said magazine, screw driving and holding means andtool, a rotatable spindle adapted to engage and support said supportingmember, an escapement device for permitting of the delivery of a screwby gravity to the screw delivery and holding means, and a bellcrank'lever for actuating said escapement device, said bell "crank leverhaving a part so located as to be tripped by a relative movement-of thescrew delivering and holding means with reference to the magazine.

5. In a screw-driving device the combination of a magazine for screws,ascrew driving tool, a means for delivering and properly holding screwsin operative relation to said tool, and a member forming the suflicientand sole support for said magazine, screw driving and holding means andtool, a rotatable spindle adapted to engage and support said supportingmember, said magazine having an escape outlet for permitting of thedelivering of the screws therethrough singly, and means for imparting ajigging movement to said magazine, so as to shake the screws toward saidoutlet 0 ening.

6. In a screw-driving device the combination of a magazine for screws, ascrew driving tool,-a means for delivering and properly holding screwsin operative relation to said tool, and a member forming the 'sufiicientand sole support for said magazine, screw driving-and holding means andtool, a rota;

table spindle adapted to engage and support said supporting member, saidmagazine having an escape outlet for permitting of the delivering of thescrews therethrough singly, an eccentric revoluble with the aforesaldsupporting member, and connected with said magazine for imparting asifting motionto the latter. 7. In a screw driving machine thecombination of a s indle, a supporting member, supported an adapted tobe/rotated by said spindle, an eccentric carried by and rotatable withsaid supporting member, a magazine for screws carried by said eccentric,and adapted to be jigged, but not rotated thereby, a screw driving toolcarried by said supporting member, means suspended from said supportingmember, and adapted to receive and deliver a screw and hold same in operative relation to said tool, and means supported by said magazine forreleasing a. screw from said magazine and delivering said screw to thereceiving and delivering means. 8. In a screw-driving apparatus thecombination of a tubular shank having at one end thereof means forenabling it to be con-' nected with a driving spindle, a magazine forscrews entirely supported by and surrounding said shank, a screw driverin alinement with or supported by said shanlqsaid screw driver being soconnected with the shank as to' be longitudinally movable relatively tosame, means for'no-rmally resisting 1 such movement in one direction, aguiding tube loosely embracing the end of said screw driver remote fromthe aforesaid tubuand from said feed'nipple, means normally 7 preventinga screw from passing through said feed nipple, and means adapted to betripped by the aforesaid relative movement of the hopper for releasingthe screw.

In testimony whereof I aflix my signature in presence of two witnesses.

FREDERIC WILLIAM RUSSELL.

Witnesses H. .G. HUGGINS, ERNEST HARKER.

